NACTO’s report, released April 28th, adds to the growing body of research that says station density is a key factor in a bikeshare system’s success. While that claim isn’t controversial in itself, NACTO’s suggestions regarding station density cause a bit more friction.

NACTO recommends that cities place bikeshare stations no more than 1,000 feet apart—that is, at a density of 28 stations per square mile. This density would put a bike share station within a five-minute walk of each resident in a city.

NACTO’s advice, in fact, is that cities should build out their bikeshare systems at a density somewhere between that of New York’s Citi Bike (the densest system in the U.S.) and Paris’ Velib (the densest system in the world).

The majority of US bike share systems are a lot more dispersed than that. Even Chicago, which has received good press for its ambitious Divvy expansion, only plans on a density that’s a fraction of NACTO’s recommendation.

Looking at ridership statistics from bikeshare systems across the US, NACTO finds, unsurprisingly, that systems are more successful when they have more stations close together. NACTO says that most bikeshare riders are convenience users, and if a system is not convenient, riders will choose another mobility option.

This has been Washington, DC’s experience. Before Capital Bikeshare, the city experimented with a precursor known as Smart Bike. Run by outdoor advertiser Clear Channel, the system was largely a failure because it had too few stations and bikes.

Today though, Capital Bikeshare is widely seen as a gold standard. Still, the system only has four stations per square mile, and advocates have called for smaller stations, placed more densely.

Bikeshare systems should fit the populations they serve

But 28-stations-per-square-mile dense? That’s a bit radical, and bikeshare expert Paul DeMaio says it should be taken with a grain of salt. “This proposed station density won’t work well in all settings, such as suburban areas, college campuses, or less dense areas,” says DeMaio.

DeMaio maintains that mega-dense station placement can actually have negative effects on a system. “Stations at too high of a density could actually have the unintended consequence of stations cannibalizing trips from the others,” he says. If trips per bike per day is the measure of of a bike hare system’s success, as NACTO maintains, more bikes and stations regardless of population density can lead to bikes being underused and stations being inactive.

NACTO says greater station density will not only make bikesharing ubiquitous, but also that it will help jurisdictions address the social equity problems that have beleaguered bikeshare systems. Low-income areas, according to NACTO, are often built out at a lower density than the system as a whole, making bikesharing a less meaningful option for residents of these neighborhoods.

Bikeshare systems could undoubtedly be denser. More convenient, walkable stations, would increase the usefulness of these systems. 28 stations per square mile, though? It’s a worthy goal, but probably unrealistic for most cities.